Electrode winding apparatuses for stacking and winding sheet-shaped electrodes and sheet-shaped separators are described, for example, in Japanese Published Unexamined Patent Application Nos. 2007-161474 and 11-40144.
Japanese Published Unexamined Patent Application No. 2007-161474 discloses a winding apparatus for winding positive and negative electrode materials (strip-shaped electrodes) with strip-shaped separators interposed (sandwiched) therebetween. The publication discloses a configuration for detecting an edge of the strip-shaped electrode in a device for correcting meandering of the strip-shaped electrodes. Japanese Published Unexamined Patent Application No. 11-40144 relates to an apparatus for winding a strip-shaped electrode, and it discloses an apparatus that has an edge position detecting means for detecting an edge position of a strip-shaped electrode and corrects the edge position based on the edge position detected by the edge position detecting means. Both of these publications show, in the drawings, a detecting unit extending so as to enclose a widthwise edge portion of the strip-shaped electrode vertically from the outer periphery.
[Patent Reference 1] Japanese Published Unexamined Patent Application No. 2007-161474 (FIG. 2)
[Patent Reference 2] Japanese Published Unexamined Patent Application No. 11-40144 (FIGS. 1 to 3)